Slub yarn product



g 1951 A. L. BREEN ETAL 2,997,837

SLUB YARN PRODUCT Filed Dec. 22, 1959 F I 6. I F I G. H 3 2 s 53$ WWWW F I 6. 111 2 W F I G. H

a 1 ms' \I46/ INVENTORS ALVIN LEONARD BREEN MARTIN' VICTOR SUSSMAN BY vinfirm ATTORNEY United States Patent O 2,997,837 SLUB YARN PRODUCT Alvin Leonard Breen, West Chester, Pa., and Martin Victor Sussman, Istanbul, Turkey, 'assignors to E. I. du Pont de Nemours and Company, Wilmington, DeL, a corporation of Delaware Filed Dec. 22, 1959, Ser. No. 861,368 Claims. (Cl. 57-439) This invention relates to a novel yarn product and process for preparing it, and more particularly to slub yarns.

According to this invention there is provided a slub yarn in which each slub contains both 8 and Z twist. Such a yarn is prepared by passing a continuous running filamentary carrier strand axially through a fluid vortex formed by a jet of fluid with velocity at least /2 sonic, thereby twisting the strand and causing it to balloon immediately upstream of the fluid vortex, wrapping a second filamentary material about the ballooning portion of the continuously running strand to form a slub and permitting the slub to be carried by the carrier strand through the fluid vortex where it is wrapped firmly about the carrier strand with both 8 and Z twist.

Typical slub yarns produced in accordance with this invention are shown in FIGURES I, I1, and II of the attached drawing. FIGURE IV illustrates schematically a preferred embodiment of the process of this invention. FIGURES V and VI illustrate one embodiment of a fluid twister which may be used in the process.

Referring to FIGURE 1, it will be apparent that the yarn in slub 1 contains Z twist in area 2 but 8 twist *in area 3. Similarly, the carrier yarn 4 contains Z twist at 5andStwistat6.

The slub yarn product illustrated in 'FIGURE 11 is parabout the carrier yarn in the direction of twist that exists upstream of the twistenwhereasthe unslubbed, but plied sections of the yarn are twisted in the twist direction that exists downstream of the twister.

FIGURE lll sh ows a slub yarn which is referred to as a crepe tail slub yarn. It is made by processing at low tension of about 3 grams or less. The high twist imparted to the yarn by an eflicient twister at this low tension causes the yarn to form branched slubs which pass through the twister.

2,997,837 Patented Aug. 29, 1961 cause slubs are even more firmly bound to the carrying yarn as the yarn carrying the slubs passes through fluid twister 143. The slub yarn product is then passed through nip rollers 147 and wound on package roll 148 which is driven by drive roll 149. In operating in accordance with this embodiment, the carrying yarn may be either staple or continuous filament yarn, and the secondary yarn, which is added to form slubs, may be short lengths of fibers or yarns or a staple or continuous filament yarn.

FIGURES V and VI show plane and end views, respectively, of a representative fluid twister useful in this invention. In this twister, axial yarn passageway 51 is substantially cylindrical in form throughout its length. A conduit for fluid S2 intercepts the yarn passageway at 5-3 at an angle of about 90 degrees to the axis thereof and is positioned so that the longitudinal axis of the fluid conduit 52 does not intersect the longitudinal axis of yarn passageway 51, as shown in FIGURE VI. When gas under pressure is passed through fluid conduit 52 so that it reaches at least /2 sonic velocity upon emerging into the yarn passageway 51, sufl'icient torque upon any yarn in the yarn passageway is created to produce a high rate of crank twisting if the yarn is maintained at a tension of less than about 15 grams. At relatively high fluid velocities less dense fluids may be employed to obtain substantially the same torque produced by a higher density fluid traveling at lower velocity. Fluid may be supplied to the fluid conduit 52 by any convenient means.

It is an important feature of this invention that during the twisting of the yarn bundle the yarn undergoes a cranking action, that is, the longitudinal axis of the yarn h describes a surface similar to the inner surface of the yarn ticularly unique in that the slub consists of yarn wrapped trated in FIGURE VI.

passageway and spaced from the inner surface of the yarn passageway by a distance equal to about the radius of the yarn bundle. This feature of the instant invention is illus- FIGURE VI illustrates direct twisting of a yarn bundle 59 in yarnpassageway 51 and shows, by arrows, that the yarn twists about its axis in the same direction as fluid flow about the inner periphery of the yarn passageway while the axis of the yarn bundle describes a surface spaced from the inner surface of the yarn passageway by adistance at least the radius of the yarn bundle, both surfaces having a common longitudinal The stability of the branched slubs can be increased by size applied to the yarn before the carrier yarn as it is cranked and twisted with the result thatsthe short lengths of filamentary material are wound tightly about the cranking (carrier) yarn and become firmly bound thereto to form slubs. Alternatively, the slubs may be formed on the carrier yarn downstream of the fluid twister but this procedure is less desirable be- "and conditions for operating them are set forth in application Serial No. 598,135, filed July 16, 1956, by Breen and Sussman. The manner in which the process conditions disclosed in that application may be employed to produce a variety of slub yarns of this invention will be apparent to one skilled in the art. For purposes of this invention it is obviously necessary to use a fluid twister having a yarn passageway sufliciently large to permit smooth passage of both carrier yarn and slubs without undue friction or drag. The process of this invention is particularly advantageous not only because of its efficiency and high production rate, but also because the fluid vortex opens up the carrier yarn bundle suffi- 4 1 pressure, continuous filament yarn which is to be used for slubbing, is allowed to contact the rotating carrier yarn threadline. The slubbing yarn is immediately wrapped about the carrier yarn and forms slubs which of Table I.

EXAMPLE II ciently to insert and intermingle slub yarn fibers between 5 consist of short sections of carrier yarn about which and among fibers of the carrier yarn, thereby producing numerous layers of the slubbing yarn are wrapped. The a slub yarn in which the slubs, in addition to their unique tension on the carrier yarn is maintained constant at betwist, are firmly attached to the carrier yarn. tween and 2.5 grams, Whereas the tension on the slub- In operating the process of this invention, yarn tension bing yarn is varied in a rapidand random fashion between is generally maintained at less than about half the break- 10 0 and 25 grams. Wrapping occurs when the IEIJSIODdIl ing tension of the yarn'being processed and preferably the slubbmg yarn drops below the tension m the carrier between about 0.1 and about 25 grams. Twisting rates yarn. Layered slubs occur when the tension in the slubequivalent to between 100,000 and 1,200,000 turns per bmg yarn approaches zer gram Th wrapping and minute are easily obtained. carrying functions of each yarn may be reversed by The following examples illustrate the invention, reversing the relative tension levels. Process conditions are shown in Example II of Table I. EXAMPLE I A fluid twister is particularly adapted to making of slub yarns, since the twister yarn passage offers little resistance Uslhg the Shown FIGURE Polymexa to the passage of a slub, whereas mechanical twisters methylene adlpahhde) yam taken m Package 0 snub the yarn over pins, wheels, etc., which would offer Passed through the feed Ions thrmlgh a h twlster oper' substantial resistance to the passage of slubs, with the ahng on 40 Pounds Per sqhere lheh ahto a wihdup result that the threadline would be subject to frequent roll, and finally to a backwindable package. Wmdup breakdowns. speed is 160 y.p.m. Tens1on 1n the threadlme is main- By Varying the tension of the carrier yam as it passes tamed h grams' through the fluid twister, in accordance with the dishhmedlately upstream of the tvhstert Pleees of staple closure in copending application Serial No. 598,135, filed yarn (1.5 denier per filament, inch viscose) are fed July 16, 1956, by Breen and Sussman the carrier yam to the f twlshhg threahhhe from hopper" is formed into an alternating twist configuration and the cohtaehhg eliahklhg tW1 St1hg,threadhhe the staP1e slubs are wrapped about this yarn so that the product is fibers. f lmmedlately entramed Into the threadlme by a slub yarn in which the carrier portion of the filaments the rapld erahkmg h and form rahfiomly Paeed possesses a variable degree of twist or possibly alternating slubs along the threadlme An enlarged illustration of twist In h yam f GUR 11 f example, h t slubbfid y is S110W11 111 FIGURE 1 T 81111) Y f carrier filament bundle between slubs has a twist opposite is novel in that the slub is held to the carrier yarn with t th t of the slubs whereas the carrier filament bundle two directions of tw1st. One end of the slub is twisted within the slubs has a twist in the same direction as the in the 8 direction, the other end is twisted in the Z direcslubs.

Table I EXAMPLE I EXAMPLE II Carrier Slub Carrier Slub Yarn material Pol y(hexamethylene adipa- Viscose..-- Poly(hexametbylene adipa- Viscose.

ruide). mide). Denieix 1.5, 3"..--. 40. Number filaments 34 34 13 Source Plm Bobbln Supply package Type of yarn Continuous Staple-.... Continuous Initial twist 1/2 Z 12 2 Feed speed (y.p.m.)-. Tension gate yi np pee -ph 20 I 1H5 91181011 it??? Q v&vr nhtst'i tenst e V Type heater N one None Air pressure (p.s.i.g.) 40 30 Twisting action Direct Direct Product characterization-.- Slub yarn Blub yarn Air passage diameter (inches) 1 hole at .040 Yarn passage diameter (inches)- .063

tion. The process conditions are shown in Example I EXAMPLE D1 The procedure of Example I is followed except that the carrier yarn tension is maintained at 3 grams. The high twist imparted to the yarn at this low tension causes the yarn to form branched slubs which pass through the twister. The product is a so-called crepe tail slub yarn as illustrated in FIGURE HI. The stability of the branched slubs can be improved by application of size to the yam before it enters the twister.

A similar slub yarn is produced by plucking a thread-"" line passing through the twister so as to create short rapid tension changes. Of course, the overall tension should be maintained low.

The examples in Table II illustrate the operation of 5 and with a variety of yarns, both natural and synthetic.

Air was used as the twisting fluid in all examples, and air velocity was at least V2 sonic.

This application is a continuation-in-part of applicafion Serial No. 598,135 filed July 16, 1956, by Breen and See footnote at end of table.

the process of this invention under various conditions Sussman.

. Table 11 Example IV Example V Carrier Slub Yarn material Dacron Orlon. Denier 250 3. Number filaments.. 50 Source Spin bobbin Type of yarn Continuous. Staple. Initial twist 0 7 Feed speed (y.p.m.) Tension gate Intermittent. Windup s eed (y.p.m.) 100 67. Tension gms.) 0-20. Process twist..- Z Z. Fluid twister FIGS. V and VL--. FIGS. V and VI. Air pressure (p.s.i.g.) 40 40. Twisting action. Direct Direct. Product characterization. Slub yarn Slub yarn. Air passage diameter (inches) .0625. Yarn passage diameter (inches) .1250 .1250.

Example VI Example VII Carrier Slub Carrier Slub Yarn material QDacron."

Staple. 0.

Intermittent.

67. 025. Z. IBIGS. V and VI. Direct. Slub yarn. .0625.- Yarn passage diameter (inches) .1250.

Example VIII Example IX Carrier Slub Carrier Slub Yarn material Dacron Acetate 0rlon." Denier 70.. 0 3. Number filaments. 34.. V Source Spin bobbm Type of yarn Continuous Staple. Initial twist... 0, Feed speed (y.p.m.)- Intermittent pickup. Windnp speed (y.p.m.) 67. Tension (gms) Process twist..- Z. Fluid twister... FIGS. V and VI. Air pressure (p. .g.) 40. Twisting action Direct. Product characterization. Slub yarn. Air passage diameter (inches). .0625. Yarn passage diameter (inches) .1250 1250 Example X Example XI Carrier Slub Carrier Slub Yarn material Nylon (bulk) Cotton middling.. Egyptian cotton. Middling cotton. Denier 70 28's cc Number filaments- 34 Source Pirn Type of yarn Continuous Staple. Initial twist..- 1 Z 0, Feed speed (y.p.m.). Tension gate Intermittent. Windup speed (y.p.m.) 67 67, Tension (gms.).. 10-20 0-20, Process twist.. Z. Fluid twister FIGS. V and VI-. FIGS. V and VI. Air pressure (p.s. .g.) 40. Twisting action Direct Direct Direct Direct. Product characterization.. Slub yarn. Slub yarn Slub yarn Slub yarn. Air passage diameter (inches). 1 hole at .0625 .0625 1 hole at .0625 .0625. Yarn passage diameter (inches) .1250 .1250 .1250 .1250.

Table Il-Continued Example XII Example XIII Oerrier Slub Carrier Slub Yarn material Dacron" Dacron. Denier 10 4.75. Number filaments ti ourcmf g 1 e o yarn mm Sta e. Irfiial twist 32.5 p Feed speed (y.p.m.) Tension gate Intermittent. Windup speed (y.p.m.) 61 Tension (gins) 510... ....5 0-20. Process twi Z Z. Fluid twister." FIGS. V and VI..- FIGS. V and VI. Air pressure (p.s.i. 40 40. Twisting action. I Direc Direct. Product characterization- Slub yarn Slub yar Slub yarn Slub yarn. Air passage diameter (inches) l'hole at .0625 .0625 1 hole at .0625 .0625. Yarn passage diameter (inches) .1250. 1250- .1250. .1250.

1 2 ply.

We claim: References Cited in the file of this patent l. A slub yarn characterized by slubs containing both 5 and Z twist.

2. The yarn of claim 1 in which the slubs are discrete and composed of staple fibers.

3. The yarn of claim 1 in which the slubs are interconnected, being composed of a continuous multifilament yarn.

4. The yarn of claim 1 in which the slubs are composed of a staple yarn.

5. The yarn of claim 1 in which the yarn between slubs possesses S and Z twist.

UNITED STATES PATENTS 2,564,245 Billion Aug. 14, 1951 25 2,751,747 Bnrleson June 26, 1956 2,846,839 Billion Aug. 12, 1958 2,869,967 Breen Jan. 20, 1959 FOREIGN PATENTS 30 355,447 Great Britain Aug. 27, 1931 

